Electrode for discharge devices



Jan. 8, 1935. P. M. HAFFCKE.

ELECTRODE FOR DSCHARGE DEVCES Filed Aug. 26, 1931 INVENTOR Pm@ M Hcgjfce n Md ATTORNEY nl mnmnn nunon umnnnunnmw UUUUUUUUDHHH nnnnu UGDHHH nnnnm UUGHHH annum UU HHH annum UUUHHH annum muni nunon UDUNMHH annum DUUHHH nunon n DUMVHHI L n cnc n n n ILJHCHHH `25 ing to'become equally distant, with the further This invention Arelates toimprovern nt in elecf ntf" i tricdischarge,jdevicesgvmarticularly to improvements in electrodes, and has special reference to 1 the provision of an `electrode for tubes' or cellsoperable at comparatively highv voltages.

A principal object of my inventionisto provid a non-sputtering, weldable electrode.V 1

A further object of myv invention is to provide i a. foraminous electrode having a plane surface whereby a discharge shallbe ofeven Value over' the entire surface thereof.

Another object of myinventiony is to provide an electrode material capablefof being formed into cylinders, or `the like, and having 1a uniform thickness at all points. L

Still another object of my invention is to make practical the use of unweldable, but otherwise useful, materials in high Yvoltage electric discharge devices. It is well `known charge between an anode and a'plurality of cathodes, unless the cathodes are equally distant from the anode, the discharges will be of unequal values, and, the voltage being sufficiently high,` the cathode nearer the anode will sputter away, tendcathode, from the anode. i I

.i The undesirable conditions above set forth are inherent in ionic discharge devices using woven wire electrodes, where the undulate surface of the mesh, ineffect, presents a group of minute electrode points rather than asmooth continuous surface. l

I am aware that a. plane surface maybe obtained by rolling and compressing a metal fabric electrode, and that in the, thermionic vacuum tube art certain advantages are claimed for electrodes of this type; however, in discharge tubes or cells of the high voltage type the plane` surface presented to the discharge should be of a non` `sputtering material and, as faras I am aware, it has not been practical to utilize electrodes of nonsputtering material such as aluminum or alloys thereof, because it is not practical to weld (for instance to support arms) material of thisgen-l eral nature. i

Referring to the accompanying drawing in which certain particular preferredforms of the `invention are shown by way of illustration,` but withoutlimiting'the invention thereto;`

Fig. 1 is an end view of `the electrode material. Fig. 2 is a plan view of Fig. 1. l Fig. 3 is a plan view ofa completed electrode structure in Figs. 1 and 2. j i Fig. 4 is another embodiment of my invention.

lDISQHAR GELPEVICESF* rnni M naatkeynamae, "assigntigty, f mesneassignmentsyto RadioRefseaich Labbral fl v.that where `there is a` dis- MlIl/lllvltiliicontemplatesacomposite foramit u lnousf electrode 1 material `j lcomprising 1 a4 plurality a of intimately joined laminations of alternate composition. In Fig. 1, 1 is a piece of woven aluminum mesh; 2 is a piece of Woven nickel fabric, which may be of somewhat finer mesh than the aluminum 1. Thek metallic sheets 1 and 2 are arranged face to face and compressed together so that their Warp and weft strands are intimately intermeshed, and the finishedysurfaces 3, 4 rendered substantially smooth.

Sections A and lEl are unrolled pieces o f aluminum and `nickel fabric; Section B shows two layers inposition for rolling. Section C shows how `the warp and weft strands become mechanically intimately intermeshed in the finished electrode material shown infsection D.

Referring to Fig. 2, where it is desired to form my composite materiall into cylindrical shape I am ,able to form anelectrode of uniform thickness by avoiding rolling'the selvedge until the material is shaped;- that is to say, incompressing the lamina- `tions I permit section A of-the fabric 1 to overlap fabric 2, while the joppositeedge, section E, of fabric 2 overlaps fabricl', I then shape the electrode and roll the edges together, thereby forming strands of fabric `1 being of softer density than those of nickel 2 will enmesh and surround the ,strands of nickel, nevertheless the nickel is not always completely lost in the aluminum in which case surface 4 may not be as smooth or as free from sputtering action as surface 3. Surface 4, formerly nickel fabric 2, serves not alone to take a weld, but lserves also to strengthen and support surface 3, obviating the use of support arms running the entire length of` the electrode-#all of which will more fully appear in connection with Fig. 4'. Electrode supports` 5 and 6 are preferably, although not necessarily, on the side opposite to that presented to the electrical discharge. l Fig. 3 is enough of a gas discharge tube, for in stance of the rectifier type, to show my new electrode in position.` 7 is an anode which may, or may not, be of the composite material ofthis invention. The outer electrode designated D is of a material within my invention. Surface 3,

as previously set forth, being the smooth perforate i supports 5 and 6 may be conveniently welded to surface 4.

Referring now to Fig.v 4 in cases where the additional strengthening and. supporting properties of the nickel are not-essential, or Where ease of welding is the only quality required, it is merely necessary to confinethe nickel lamination to the region of .the weld as at D, which case section Srmay be a'sin'gle--Iayer of a rolled aluminum or other suitable material. n* l As substitutions of material and other modifications of my invention willfsuggest themselves to f those skilled in the art to which my invention pertains, it is to be understcca tiit-th 'fore-'- going is to be interpretedfas"illustrative not.

pended claims and by the riorl art;l

What is claimed is: 1,1-

1. A composite electrode for electri in limiting sense except as required by the apdischarge devices comprising `a' plurality' of' intimately' cbmpressed foraminous .metallic laminas, 'at-least one said structure: f

of said lamin being composed substantially of aluminum and another of a weldable material.

2. A composite foraminous electrode for electric discharge devices comprising a. fabric of aluminumV intimately compressed to a fabric of nickel.

3. A non-sputtering weldable electrode for electricv discharge devices comprising asheet; of woven nickel fabric and a sheet of-,wovenaluminum fabric arranged face to face, and compressed togetheriwith their warp and weft strands intimately ntermeshed. .Y `Lllnelectrode for electric discharge devices comprisingga composite cylindrical structure of feminin,011sV laminare compressed together, one of said-laminas being' composed substantially of aluandmanother of nickel, the linear edge 'ofl the aluminum overlapping the nickel at the point; .of'joi-nture whereby the jointed selvedge is rendered integral with the plane of the'body of 20 PHrLIP M. 

